ABSTRACT
AIM To investigate the protective effects and the mechanism of corosolic acid on doxorubicin-induced cardiotoxicity in H9c2 cardiomyocytes.METHODS To screen and determine the effective concentration of corosolic acid,the injury models of H9c2 cardiomyocytes established by 1 μmol/L doxorubicin were exposed to 24 h different concentrations of corosolic acid,followed by detections of their cell activity by MTT method;their cell apoptosis morphology by Hoechst 33342 staining method;their cell apoptosis rate by Annexin V-FITC/PI double staining method;their intracellular ROS level by DCFH-DA probe;their intracellular iron level by iron ion colorimetry;and their protein expressions of Bax,Bcl-2,cleaved-caspase3,Nrf2,GPX4 and Ptgs2 by Western blot.RESULTS Upon the doxorubicin-induced injury models of H9c2 cardiomyocytes,corosolic acid improved their viability and survival rate(P<0.05),decreased their levels of ROS and Fe2+ and the apoptosis rate(P<0.05),up-regulated the protein expressions of Bcl-2,Nrf2 and GPX4(P<0.05),and down-regulated the protein expressions of Bax,cleved-caspase 3 and Ptgs2(P<0.05).CONCLUSION Corosolic acid can inhibit the ROS level and apoptosis of doxorubicin-induced injury models of H9c2 cardiomyocytes,and the iron death as well via activating Nrf2/GPX4 pathway.